High maintenance: The sunken foundation of a house in Urayasu, Chiba, caused by the Great East Japan Earthquake, tilts the building to the left. It can cost about ¥10 million to jack up a sunken home and make it level again. | PHILIP BRASOR PHOTO

Your dream home could become a quake nightmare

Like other people in the Tokyo metropolitan area who were living in a high-rise when the March 11 earthquake struck, we subsequently decided to move.

The problem was not the structural integrity of our building, which was not damaged at all. According to a survey by the Condominium Management Companies Association, even high-rises in the Tohoku region “performed” excellently. None collapsed, and only 1.6 percent required “large-scale” repairs. More than 80 percent sustained only slight cosmetic damage or none at all.

For us the issue was more a matter of quality of life. Elevators automatically shut down during an earthquake and can only be turned on again by a certified technician. It might be days before they are operational again. Also, when electrical power is lost through either damage or design (planned blackouts), high-rise living is virtually impossible, and not just because of elevators: Water supply and sewage systems require power.

So in the months since the quake and the Fukushima nuclear power plant disasters we intensified the off-and-on search we started many years ago for a place to buy, whether it be a single-family house or a condominium. But in the end we stuck with renting, because if the disaster proved anything, it’s that you can lose everything in a matter of minutes and still have to pay for it. Many homeowners from the stricken areas still have outstanding loans on the houses that were destroyed.

For this reason, we assumed people would be more apprehensive about buying, but real estate agents we talked to said that while business fell off immediately after March 11 it was back to pre-quake levels by early April. If anything changed, it was the criteria that potential buyers used to decide on a property. In terms of both rentals and sales, many people simply preferred being closer to the ground. “First-floor units are really popular now,” one agent told us, a notable switch from before the quake, when higher floors commanded higher prices.

The sturdiness of multi-residence buildings is subject to stricter codes that went into effect in 1981. Sixty “mid-level” buildings (14 stories or less) in Sendai, Miyagi Prefecture, have been condemned since the quake, but all were constructed in the 1970s. Structures are now built to absorb the energy of an earthquake, which is why high-rises sway rather than shake. Some of the state-of-the-art condos we visited have rubber dampers in their foundations, which absorb the energy more efficiently and diminish the amount of swaying. These menshin condos are not only more expensive than conventional ones, they also cost more down the line, since the dampers have to be replaced about 20 years after the building is constructed. Depending on how many units there are, this can cost each tenant between ¥2 and ¥3 million.

Many single-family homes built in recent years are also earthquake-proofed in that their frames are bolted to their foundations. However, as we learned while looking at properties in Tochigi Prefecture, some homeowners have opted to reinforce the structure with crossbeams in the walls or, in the case of one restaurant we saw, outside the walls. (The metal braces were incorporated into the decor)

But structural integrity is only half the story. Equally important, if not more, is the land the building sits on. The quake caused liquefaction in many places in the Kanto region, notably Urayasu and Abiko in Chiba Prefecture and Kuki in Saitama Prefecture, where houses sank or tilted. It costs about ¥10 million to have a sunken house jacked up and made level again, and according to experts it will likely sink again when another large earthquake strikes.

The land surrounding Tokyo Bay, from Haneda Airport all the way around to Kimitsu, Chiba Prefecture, is man made. Other problem areas are the low-lying sections of eastern Tokyo along the Edo and Sumida Rivers reaching up into Saitama Prefecture. The media has reported increased interest in properties in western Tokyo, which is considered more geologically solid than other parts of the metropolitan area.

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What to ask when looking for an earthquake-proof dwelling in Japan

• Was the building constructed before or after 1981?
• Was the property under the residence once marshland, landfill or leveled ground?
• Has the house been bolted to its foundations?
• Does it have braces in the walls?
• For a condominium, how much is the shuzenhi (repair fee)?
• Is the repair fund for the condominium enough to cover damage from quakes or liquefaction?

Realtors aren’t going to be completely forthright about the liquefaction potential of the properties they’re selling, so buyers need to study the topographical history of the neighborhood. Was the subdivision developed on marshland or rice paddies? If the name of the area contains “numa” (swamp) or some other kanji indicating water, it may be unstable. Developers often change the name of an address to cover up this fact, usually to something with words like “oka” (hill) or “dai” (plateau). Also, 74 percent of Japan is mountainous, so many housing developments are built on leveled land, and it’s important to know if the land is kiri-do or mori-do. Kiri-do means the top of a rise was sliced off, whereas mori-do decribes a valley that was filled in. Mori-do is unstable since it takes decades for the soil to settle, and if an earthquake occurs in the meantime, liquefaction and sinkholes can occur.

Because condominiums are stabilized by piles driven deep into the ground, many people believe they are not susceptible to liquefaction. But as the situation in Urayasu showed, liquefaction can do harm in other ways. Many condos were without gas, water and sewerage for months because those lifelines are buried underground. Some residents are still using portable toilets. The cost of repairing these utilities can run into the billions of yen for just one building, which is why potential buyers should pay close attention to the mandatory shuzenhi, or repair fee, that is collected every month. Some developers purposely set the shuzenhi low in order to attract buyers, and those properties are now having problems because they don’t have enough funds accumulated to pay for damage caused by liquefaction.

Experts predicted that property values throughout greater Tokyo would plunge after the quake. According to the business magazine Diamond, prices have dipped, but not enough to make a difference. Even properties in Urayasu are only off about 10 percent from their pre-quake prices. Such a situation sounds counter-intuitive. The media has reported that many owners of high-rises along the waterfront are selling or trying to sell. However, they are not necessarily going back to renting.

Coincident with the spike in older condos going on the market there has also been a spike in sales of new condos. Potential buyers, hearing that the disaster upset the supply of housing materials, apparently believe that it will soon lead to higher prices and so they have hastened to sign contracts, regardless of any risks of future earthquakes. Consumers always think of the money they might lose now rather than the money they might lose tomorrow.

Home Truths is the first in a series of articles concerning housing and property issues, which will run every first Tuesday of the month. Philip Brasor and Masako Tsubuku blog about Japanese housing at catforehead.wordpress.com.